Patent GB-1411470-A (GB)
Title: Sprinkler installation
IPC: A62C35/64
Filed: 1973-11-12
Abstract: 1411470 Automatic sprinkler systems WALTHER & CIE AG 12 Nov 1973 [11 Nov 1972] 52502/73 Heading A5A A sprinkler system comprises at least one sprinkler which automatically open in response to fire hazard conditions, a fire warning system which operates a sprinkler supply valve in response to a fire warning signal, and auxiliary means operable on failure of the fire warning system to render the sprinkler supply valve operative in response to opening of the sprinkler. The fire warning system may be electrical, pneumatic or mechanical. In Fig 1 pipe system 18 is filled with compressed air and connected to closed sprinklers (not shown). The alarm valve or pre-action valve 1 is operated not by the air pressure but by a separate fire warning system. Valve 1 links sprinkler pipe 18 with water supply pipe 19 and is provided with pneumatically controlled diaphragm chamber 2 which holds valve disc 21 closed by means of lever mechanism 20; water is removed by pipe system 22. Leading to chamber 2 is pipe 17 which is connected to pipe 15, the latter in turn being connected to pipe 18 via pipe 28, and pipe 17 also being connected to 18 via pipe 23. Pipe 18 is supplied with compressed air via pipe 15, the latter being provided with manual shut-off valve 3, throttle valve 4 and non-return valve 5. Pipe 23 also includes shut-off valve 6, throttle valve 7 and non-return valve 8. Pipe 14 branching from pipe 17 is provided with magnetic valve 11 connected to the fire warning system of Fig 2. Further pipe 16 is connected with sprinkler pipe 18 via pipe 23, and to pipe 17, and is provided with magnetic valve 12 connected to the fire warning system and with non-return valve 25. Pipe 23 is provided with pressure guage 9 and pressureoperated switch 10. Pressure-operated switch 10 gives an alarm when valve 1 is opened. Normally valve 1 is maintained closed by the compressed air in chamber 2. Pipe system 18 is also filled with compressed air via valves 6, 7, 8. Magnetic valves 11 and 12 and shutoff valve 26 in pipe 28 are closed. When the fire warning system (of Fig 2) responds magnetic valve 11 opens and relieves pipes 14 and 17. At a predetermined pressure drop, e.g. 1 atm, valve 1 opens and water passes to sprinkler pipe 18. If one or more sprinklers has also been actuated the extinguishant is discharged therefrom. Opening of valve 1 also raises the alarm via a water turbine (not shown) and also via switch 13. If only one sprinkler opens, a pressure drop occurs in pipe 18 and is signalled at 10. If the current supply fails or there is another fault in the fire warning system magnetic valve 12 opens automatically and connects pipe 18 with control pipes 14, 15, 17. If a sprinkler then opens an air pressure drop occurs as before, the drop being propagated via valve 12 to chamber 12 to open valve 1. Fig 2 shows the fire warning system. Current is supplied from 29 via line 30 to warning device 31, and is also supplied via line 34 to maintain magnetic valve 12 closed. In the event of fire device 31 establishes a connection between lines 30 and 32 and transmits a signal to control device 35. The latter then supplies current to open magnetic valve 11 via line 33, and simultaneously deprives line 34 of current so that valve 12 also opens. Should current supply 29 fail line 34 is again deprived of current, and valve 12 opens in any case.